Variables - CSV expansion in dropdown

Is it possible to have a dashboard filter expand a CSV into discrete values in the dropdown on the dashboard?

I have a tag in both InfluxDB and ElasticSearch datasources that contains a comma separated list of roles a server performs (e.g. web, sql, various product services). If I have two servers one with “Web,SQL” as a role tage and the other with “Web,Print” - I’d like to have a dropdown on my dashboard with the option [Web], [SQL], [Print] and [All].

Is there a way to do this in Dashboard Variable configuration without prior knowledge of possible values?